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-rw-r--r--src/arch/arm/CodeGen.zig103
1 files changed, 63 insertions, 40 deletions
diff --git a/src/arch/arm/CodeGen.zig b/src/arch/arm/CodeGen.zig
index e211f9d7bc..7f0cecc14d 100644
--- a/src/arch/arm/CodeGen.zig
+++ b/src/arch/arm/CodeGen.zig
@@ -4,7 +4,6 @@ const mem = std.mem;
const math = std.math;
const assert = std.debug.assert;
const Air = @import("../../Air.zig");
-const Zir = @import("../../Zir.zig");
const Mir = @import("Mir.zig");
const Emit = @import("Emit.zig");
const Liveness = @import("../../Liveness.zig");
@@ -3059,40 +3058,39 @@ fn brVoid(self: *Self, block: Air.Inst.Index) !void {
}
fn airAsm(self: *Self, inst: Air.Inst.Index) !void {
- const air_datas = self.air.instructions.items(.data);
- const air_extra = self.air.extraData(Air.Asm, air_datas[inst].ty_pl.payload);
- const zir = self.mod_fn.owner_decl.getFileScope().zir;
- const extended = zir.instructions.items(.data)[air_extra.data.zir_index].extended;
- const zir_extra = zir.extraData(Zir.Inst.Asm, extended.operand);
- const asm_source = zir.nullTerminatedString(zir_extra.data.asm_source);
- const outputs_len = @truncate(u5, extended.small);
- const args_len = @truncate(u5, extended.small >> 5);
- const clobbers_len = @truncate(u5, extended.small >> 10);
- _ = clobbers_len; // TODO honor these
- const is_volatile = @truncate(u1, extended.small >> 15) != 0;
- const outputs = @bitCast([]const Air.Inst.Ref, self.air.extra[air_extra.end..][0..outputs_len]);
- const args = @bitCast([]const Air.Inst.Ref, self.air.extra[air_extra.end + outputs.len ..][0..args_len]);
-
- if (outputs_len > 1) {
- return self.fail("TODO implement codegen for asm with more than 1 output", .{});
- }
- var extra_i: usize = zir_extra.end;
- const output_constraint: ?[]const u8 = out: {
- var i: usize = 0;
- while (i < outputs_len) : (i += 1) {
- const output = zir.extraData(Zir.Inst.Asm.Output, extra_i);
- extra_i = output.end;
- break :out zir.nullTerminatedString(output.data.constraint);
- }
- break :out null;
- };
+ const ty_pl = self.air.instructions.items(.data)[inst].ty_pl;
+ const extra = self.air.extraData(Air.Asm, ty_pl.payload);
+ const is_volatile = @truncate(u1, extra.data.flags >> 31) != 0;
+ const clobbers_len = @truncate(u31, extra.data.flags);
+ var extra_i: usize = extra.end;
+ const outputs = @bitCast([]const Air.Inst.Ref, self.air.extra[extra_i..][0..extra.data.outputs_len]);
+ extra_i += outputs.len;
+ const inputs = @bitCast([]const Air.Inst.Ref, self.air.extra[extra_i..][0..extra.data.inputs_len]);
+ extra_i += inputs.len;
const dead = !is_volatile and self.liveness.isUnused(inst);
const result: MCValue = if (dead) .dead else result: {
- for (args) |arg| {
- const input = zir.extraData(Zir.Inst.Asm.Input, extra_i);
- extra_i = input.end;
- const constraint = zir.nullTerminatedString(input.data.constraint);
+ if (outputs.len > 1) {
+ return self.fail("TODO implement codegen for asm with more than 1 output", .{});
+ }
+
+ const output_constraint: ?[]const u8 = for (outputs) |output| {
+ if (output != .none) {
+ return self.fail("TODO implement codegen for non-expr asm", .{});
+ }
+ const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(self.air.extra[extra_i..]), 0);
+ // This equation accounts for the fact that even if we have exactly 4 bytes
+ // for the string, we still use the next u32 for the null terminator.
+ extra_i += constraint.len / 4 + 1;
+
+ break constraint;
+ } else null;
+
+ for (inputs) |input| {
+ const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(self.air.extra[extra_i..]), 0);
+ // This equation accounts for the fact that even if we have exactly 4 bytes
+ // for the string, we still use the next u32 for the null terminator.
+ extra_i += constraint.len / 4 + 1;
if (constraint.len < 3 or constraint[0] != '{' or constraint[constraint.len - 1] != '}') {
return self.fail("unrecognized asm input constraint: '{s}'", .{constraint});
@@ -3101,11 +3099,25 @@ fn airAsm(self: *Self, inst: Air.Inst.Index) !void {
const reg = parseRegName(reg_name) orelse
return self.fail("unrecognized register: '{s}'", .{reg_name});
- const arg_mcv = try self.resolveInst(arg);
+ const arg_mcv = try self.resolveInst(input);
try self.register_manager.getReg(reg, null);
- try self.genSetReg(self.air.typeOf(arg), reg, arg_mcv);
+ try self.genSetReg(self.air.typeOf(input), reg, arg_mcv);
+ }
+
+ {
+ var clobber_i: u32 = 0;
+ while (clobber_i < clobbers_len) : (clobber_i += 1) {
+ const clobber = std.mem.sliceTo(std.mem.sliceAsBytes(self.air.extra[extra_i..]), 0);
+ // This equation accounts for the fact that even if we have exactly 4 bytes
+ // for the string, we still use the next u32 for the null terminator.
+ extra_i += clobber.len / 4 + 1;
+
+ // TODO honor these
+ }
}
+ const asm_source = std.mem.sliceAsBytes(self.air.extra[extra_i..])[0..extra.data.source_len];
+
if (mem.eql(u8, asm_source, "svc #0")) {
_ = try self.addInst(.{
.tag = .svc,
@@ -3128,18 +3140,29 @@ fn airAsm(self: *Self, inst: Air.Inst.Index) !void {
break :result MCValue{ .none = {} };
}
};
- if (outputs.len + args.len <= Liveness.bpi - 1) {
+
+ simple: {
var buf = [1]Air.Inst.Ref{.none} ** (Liveness.bpi - 1);
- std.mem.copy(Air.Inst.Ref, &buf, outputs);
- std.mem.copy(Air.Inst.Ref, buf[outputs.len..], args);
+ var buf_index: usize = 0;
+ for (outputs) |output| {
+ if (output == .none) continue;
+
+ if (buf_index >= buf.len) break :simple;
+ buf[buf_index] = output;
+ buf_index += 1;
+ }
+ if (buf_index + inputs.len > buf.len) break :simple;
+ std.mem.copy(Air.Inst.Ref, buf[buf_index..], inputs);
return self.finishAir(inst, result, buf);
}
- var bt = try self.iterateBigTomb(inst, outputs.len + args.len);
+ var bt = try self.iterateBigTomb(inst, outputs.len + inputs.len);
for (outputs) |output| {
+ if (output == .none) continue;
+
bt.feed(output);
}
- for (args) |arg| {
- bt.feed(arg);
+ for (inputs) |input| {
+ bt.feed(input);
}
return bt.finishAir(result);
}